import T from 'ant-design-vue/es/table/Table'
import get from 'lodash.get'

export default {
    data() {
        return {
            needTotalList: [],

            selectedRows: [],
            selectedRowKeys: [],

            localLoading: false,
            localDataSource: [],
            localPagination: Object.assign({}, this.pagination)
        }
    },
    props: Object.assign({}, T.props, {
        rowKey: {
            type: [String, Function],
            default: 'key'
        },
        data: {
            type: Function,
            required: true
        },
        pageNum: {
            type: Number,
            default: 1
        },
        pageSize: {
            type: Number,
            default: 15
        },
        showSizeChanger: {
            type: Boolean,
            default: false
        },
        size: {
            type: String,
            default: 'default'
        },
        // 展开的图标显示在哪一列
        expandIconColumnIndex: {
            type: Number,
            default: 0
        },
        /**
         * alert: {
         *   show: true,
         *   clear: Function
         * }
         */
        alert: {
            type: [Object, Boolean],
            default: null
        },
        rowSelection: {
            type: Object,
            default: null
        },
        /** @Deprecated */
        showAlertInfo: {
            type: Boolean,
            default: false
        },
        showPagination: {
            type: String | Boolean,
            default: 'auto'
        },
        /**
         * enable page URI mode
         *
         * e.g:
         * /users/1
         * /users/2
         * /users/3?queryParam=test
         * ...
         */
        pageURI: {
            type: Boolean,
            default: false
        }
    }),
    watch: {
        'localPagination.current'(val) {
            this.pageURI && this.$router.push({
                ...this.$route,
                name: this.$route.name,
                params: Object.assign({}, this.$route.params, {
                    page: val
                })
            })
        },
        pageNum(val) {
            Object.assign(this.localPagination, {
                current: val
            })
        },
        pageSize(val) {
            Object.assign(this.localPagination, {
                pageSize: val
            })
        },
        showSizeChanger(val) {
            Object.assign(this.localPagination, {
                showSizeChanger: val
            })
        },
        // 同步正在加载中的状态
        loading(val) {
            this.localLoading = val
        }
    },
    created() {
        const {page} = this.$route.params
        const localPageNum = this.pageURI && (page && parseInt(page)) || this.pageNum
        this.localPagination = ['auto', true].includes(this.showPagination) && Object.assign({}, this.localPagination, {
            current: localPageNum,
            pageSize: this.pageSize,
            showSizeChanger: this.showSizeChanger
        }) || false
        // console.log('this.localPagination', this.localPagination)
        this.needTotalList = this.initTotalList(this.columns)
        this.loadData()
    },
    methods: {
        /**
         * 表格重新加载方法
         * 如果参数为 true, 则强制刷新到第一页
         * @param Boolean bool
         */
        refresh(bool = false) {
            bool && (this.localPagination = Object.assign({}, {
                current: 1, pageSize: this.pageSize
            }))
            this.loadData()
        },
        /**
         * 加载数据方法
         * @param {Object} pagination 分页选项器
         * @param {Object} filters 过滤条件
         * @param {Object} sorter 排序条件
         */
        loadData(pagination, filters, sorter) {
            this.localLoading = true
            const params = Object.assign({
                page: (pagination && pagination.current) ||
                    this.showPagination && this.localPagination.current || this.pageNum
                // pageSize: (pagination && pagination.pageSize) ||
                //   this.showPagination && this.localPagination.pageSize || this.pageSize
                },
                (sorter && sorter.field && {
                    sortField: sorter.field
                }) || {},
                (sorter && sorter.order && {
                    sortOrder: sorter.order
                }) || {}, {
                    ...filters
                }
            )
            // console.log('params', params)
            const result = this.data(params)
            // 对接自己的通用数据接口需要修改下方代码中的 r.page, r.totalCount, r.data
            // eslint-disable-next-line
            if ((typeof result === 'object' || typeof result === 'function') && typeof result.then === 'function') {
                result.then(r => {
                    this.localPagination = this.showPagination && Object.assign({}, this.localPagination, {
                        current: r.current_page, // 返回结果中的当前分页数
                        total: r.total, // 返回结果中的总记录数
                        showSizeChanger: this.showSizeChanger,
                        pageSize: (pagination && pagination.pageSize) ||
                            this.localPagination.pageSize
                    }) || false
                    // 为防止删除数据后导致页面当前页面数据长度为 0 ,自动翻页到上一页
                    if (r.data.length === 0 && this.showPagination && this.localPagination.current > 1) {
                        this.localPagination.current--
                        this.loadData()
                        return
                    }

                    // 这里用于判断接口是否有返回 r.totalCount 且 this.showPagination = true 且 page 和 pageSize 存在 且 totalCount 小于等于 page * pageSize 的大小
                    // 当情况满足时，表示数据不满足分页大小，关闭 table 分页功能
                    try {
                        if ((['auto', true].includes(this.showPagination) && r.total <= (r.current_page * this.localPagination.pageSize))) {
                            this.localPagination.hideOnSinglePage = true
                        }
                    } catch (e) {
                        this.localPagination = false
                    }
                    // console.log('loadData -> this.localPagination', this.localPagination)
                    this.localDataSource = r.data // 返回结果中的数组数据
                    this.localLoading = false
                })
            }
        },
        initTotalList(columns) {
            const totalList = []
            columns && columns instanceof Array && columns.forEach(column => {
                if (column.needTotal) {
                    totalList.push({
                        ...column,
                        total: 0
                    })
                }
            })
            return totalList
        },
        /**
         * 用于更新已选中的列表数据 total 统计
         * @param selectedRowKeys
         * @param selectedRows
         */
        updateSelect(selectedRowKeys, selectedRows) {
            this.selectedRows = selectedRows
            this.selectedRowKeys = selectedRowKeys
            const list = this.needTotalList
            this.needTotalList = list.map(item => {
                return {
                    ...item,
                    total: selectedRows.reduce((sum, val) => {
                        const total = sum + parseInt(get(val, item.dataIndex))
                        return isNaN(total) ? 0 : total
                    }, 0)
                }
            })
        },
        /**
         * 清空 table 已选中项
         */
        clearSelected() {
            if (this.rowSelection) {
                this.rowSelection.onChange([], [])
                this.updateSelect([], [])
            }
        },
        /**
         * 处理交给 table 使用者去处理 clear 事件时，内部选中统计同时调用
         * @param callback
         * @returns {*}
         */
        renderClear(callback) {
            if (this.selectedRowKeys.length <= 0) return null
            return (
                <a style="margin-left: 24px" onClick={() => {
                    callback()
                    this.clearSelected()
                }}>清空</a>
            )
        },
        renderAlert() {
            // 绘制统计列数据
            const needTotalItems = this.needTotalList.map((item) => {
                return (<span style="margin-right: 12px">
          {item.title}总计 <a
                    style="font-weight: 600">{!item.customRender ? item.total : item.customRender(item.total)}</a>
        </span>)
            })

            // 绘制 清空 按钮
            const clearItem = (typeof this.alert.clear === 'boolean' && this.alert.clear) ? (
                this.renderClear(this.clearSelected)
            ) : (this.alert !== null && typeof this.alert.clear === 'function') ? (
                this.renderClear(this.alert.clear)
            ) : null

            // 绘制 alert 组件
            return (
                <a-alert showIcon={true} style="margin-bottom: 16px">
                    <template slot="message">
                        <span style="margin-right: 12px">已选择: <a
                            style="font-weight: 600">{this.selectedRows.length}</a></span>
                        {needTotalItems}
                        {clearItem}
                    </template>
                </a-alert>
            )
        }
    },

    render() {
        const props = {}
        const localKeys = Object.keys(this.$data)
        const showAlert = (typeof this.alert === 'object' && this.alert !== null && this.alert.show) && typeof this.rowSelection.selectedRowKeys !== 'undefined' || this.alert
        Object.keys(T.props).forEach(k => {
            const localKey = `local${k.substring(0, 1).toUpperCase()}${k.substring(1)}`
            if (localKeys.includes(localKey)) {
                props[k] = this[localKey]
                return props[k]
            }
            if (k === 'rowSelection') {
                if (showAlert && this.rowSelection) {
                    // 如果需要使用alert，则重新绑定 rowSelection 事件
                    // console.log('this.rowSelection', this.rowSelection)
                    props[k] = {
                        ...this.rowSelection,
                        selectedRows: this.selectedRows,
                        selectedRowKeys: this.selectedRowKeys,
                        onChange: (selectedRowKeys, selectedRows) => {
                            this.updateSelect(selectedRowKeys, selectedRows)
                            typeof this[k].onChange !== 'undefined' && this[k].onChange(selectedRowKeys, selectedRows)
                        }
                    }
                    return props[k]
                } else if (!this.rowSelection) {
                    // 如果没打算开启 rowSelection 则清空默认的选择项
                    props[k] = null
                    return props[k]
                }
            }
            this[k] && (props[k] = this[k])
            return props[k]
        })
        const table = (
            <a-table {...{props, scopedSlots: {...this.$scopedSlots}}} onChange={this.loadData}
                     onExpand={(expanded, record) => {
                         this.$emit('expand', expanded, record)
                     }}>
                {Object.keys(this.$slots).map(name => (<template slot={name}>{this.$slots[name]}</template>))}
            </a-table>
        )
        return (
            <div class="table-wrapper">
                {showAlert ? this.renderAlert() : null}
                {table}
            </div>
        )
    }
}
